System of electrical distribution.



No. 870,149. PATENTED NOV. 5. 1907. J. L. WOODBRIDGE.

SYSTEM OF ELECTRICAL DISTRIBUTION.

APPLIOATION FILED APE.19, 1905.

UNITED STATES PATENT OFFICE.

JOSEPH LESTER WOODBRIDGE, OF PHILADELPHIA, PENNSYLVANIA.

,SYSTEM OF ELECTRICAL DISTRIBUTION To all whom it may concern:

Be it known that I, JOSEPH LESTER WOODBRInGi-z, a

- citizen of the United States, and a-residcnt of Philadelphia, in the county of Philadelphia and State oi Pennsylvania, have inyented a certain new and useful System of Electrical. Distribution, of which the following is a specification. I

The invention has relation to those systems in which use is made of a battery and its booster in connection with both alternating current and direct current lines. Objects of the present invention are to make the booster-control responsive to variations in the alternating current circuit, or otherwise stated to control the field of a booster in such a way that it responds to changes of load in the alternating current circuit; to effect regulation accurately and etliciently; and to provide apparatus for the purposes stated, which shall be simple, reliable and durable. and also rapid in its ac- 7 tion.

To these and other ends hereinafter set forth the invention comprises the improvements to be presently described and finally claimed.

The nature, characteristic features and scope of the invention will be more fully understood from the following description taken in connection with the accompanying drawings forming part hereof and in which I Figure l, is a diagrammatic view illustrating a systern of distribution embodying features of the invention. Fig. 2, is a diagram which will be hereinafter referred to for purposes of explanation. i In th e drawings l, is a source of alternating current power which is delivered to the transmission lines 2.

3, is a rotary transformer taking current from the alternating current lines 2 and delivering direct current to the circuit 4-6, or takin current from the direct current lines 4--5, and delivering alternating current to the alternating current lines 2.

7 and G are alternating current and direct current translating devices respectively arranged in the approprinte circuits.

8, is a batteryprovider] with a booster 5), (which may be suitably driven) and connected across the direct current circuit 4- 5.

l0, a device for controlling the field ll, of the booster and it responsive to changes of current in the illtcrimtingcurrent lines 2 and is constructed as follows: 2, 1 primary windings connected (as short n in pure) n series with the alt rnating current lines 22 and adapt cd to -12'rnlt1uun rotztting magnetic field in the magnetic constituting the magnetic circuit. 14, arywinding in inductive relation to the magnetic field produced by the primary windings l2 and to this secondary winding is connected acounnutator 15. Both the Speciflcati on of Letters Patent. Application filed April 19, 1905- i i l I I l l l i l l 1 is a second- 1 Patented Nov. 5, 1907. Serial No. 256.477.

windings l2 and .14 and the commutator 15 are stationary. The rotating field will produce an electronnotivc force in the secondary winding 14 and a potential difference between opposite bars of the commutator 15 whose point of maximum value will rotate with the field.

l6 and 17 are direct current brushes revolving about the commutator and maintained at the point of maximum electrounritivefbrce by the synchronous motor N of the revolving field type as l'ie1'e.sl1oWI1 driven in syncllronism with the revolving fieldby current from the alternating current circuit 2. I

19 and 20 are direct current brushes arranged at rigb t angles to the brushes 16 and 17 and rotated therewith The brushes l9 and 20 are electrically connected through the field winding ll of the booster by the slip rings 21 and 22 and the brushes l6 and 17 are electrically connected to points 4 and 5 in the direct current circuit by the slip rings 23 and 24. Before proceeding to describe the operation of the apparatus which has been explained, a brief explanation will be given in connection with Fig, 2, Assume that A is a winding and that B, and C, are brushes brarin g upon this winding or upon a commutator connected \vith'it and to which brushes B and C, a direct current electro-inotive force is applied. Current will tend to flow through the winding from B, to O, and this current will produce a magnetic field I), in thedircction B-(/. When thev brushes B, and C, are rotated this field D, will produce an electro-motive force it and following it in. its rotation. For the sake of description this electro-motive force may be taken to exist between the points E-F. are applied brushes rotating with the brushes B C, and connected together electrically as by the conductor G, current will flow through the conductor G, and wvinding A, between the points F and E. This current in the winding l-)Fnnd-this field rotating with the brushes produces an (-lectro-nioti'm iorcc at tliebrushcs 1P0 counter to the electro-uiotivc force applied to these brushes B and C and substantially equal to it, so the t only enough cur} rent due to the (:lCtlFQdllOllVli force applied attire brushes BC travmses the winding to maintain the conditions which have been described. From this it follows that ii the potential difference between B and C is substantially constant and the proper strength of field H be produced by some external source to oppose the passage of current through the winding from B to C there will be no current traversing the conductor G. If the external source of field excitation be'wcakened sullicicut current will traverse the conductor Gin such direction as to cooperate with the external excitation so as to "maintain the field strength H; and if the external source of excitation be strengthened, current will traverse the cond uctor G in the at right angles to i If to the points E-F,

produces a field. H, in the direction opposite direction and in amount sufiicient by opposing the external excitation to still maintain thefield strength H. Thus the current in G will respond in amount and direction to variations in the external source. of excitation.

A description of the mode of operation of the apparatus illustrated in Fig. 1, will now be given.

It the current in the alternating current line 2 is sufiicient to produce a direct current voltage at the brushes 16 and 17 equal to that on the direct current circuit 4--5 there will be no current in the booster field 11. That is to say in connection with the description given oi Pig. 2, the hold H, will be maintained from an outside source (imaginary, having regard to Fig. 2, but possible by reason of the coils 12, in Fig. l) of such strength that there is developed a connter-electro-motive force equal to theelcctro-motive force applied at 13-0. If the alternating current increases, for example, by reason of the presence of an additional load on either circuit, since they are in effect connected together through the rotary 3, current will flow from the brushes 16 and 17 into the direct current circuit in such a direction as to cause a field in the direction 1617 and a consequent electro-motive force at the brushes 19'and 20,w11ich will excite the booster field in a direction to cause the battery to discharge. In connection with Fig. 2, this may be likened to an addition to the field H from an outside source. If the. alternating current decreases as by reason of a decrease in load, the field along the line 10 and 17 will be reversed in dircc'tiomrcvcrsing the current in the booster field and causing the battery to charge. By changing the potential (which may be anything from zero up) applied to the brushes 16 and 17, or by changing the ratio of turns in the windings 12 and 14, different average loads in the alternating current line 2-2 may be provided for: and such changes may be accomplished in a variety of well known ways.

It will be obvious to those skilled in the art to which the invention relates that modifications may bemade in detail without departing from the spirit thereof, hence the invention is not limited further than the prior state of the art may require, but

Having thus described the nature and objects oi my invention, what I claim as new and desire to secure by Letters Patent is: I

1. The combination of a source of alternating current power andits transmission lines including a suitable con- "erier and its direct current transmission lines a batteryand its booster, and a booster controller comprising primary and secondary windings arranged in inductive relation and whereof the latter is provided with a coln inutator and the former" is opcratively arranged in the alternating current circuit, and also comprisingoommutator brushesconnected respectively with the direct substantially as described.

2. The combination of a regulating coil, alternating and direct current: circuits having connected between them a suitable converter, windings in inductive relation and whereof the primary. appertains to the alternating circuit and the secondary is provided with a ,conimutator, and brushes respectively appertaining to the coil and to the direct current circuit, substantially as described.

-5l. A magnetic circuit all parts of which are relatively fixed, alternating current and direct. current means for producing;- a resultant magnetic field in said circuit, a regulating coil, and means for applying to the regulating coil the eleetro-motiyo-force produced by the resultant field.

4. The combination of an alternating, current circuit, a fixed primary winding operativeiy arranged therein for producing a rotary magnetic field, a fixed sccondarywind ing in inductive relation to the magnetic field and pro-I vided with a fixed commutator,commutator brushes whereof some are provided with a rexulaiina circuit, means for applying constant: direct current potential to. the other cnnmutator brushes. and means for rotating all the brushes in syncbronism with the rotary field, substantially as described.

5. An alternating current source, a magnetic circuit, means for applying to the magnciic circuit exciting current from the source. a winding in inductive relation to the magnetic circuit. a eonnnutator for said winding. two angulurly displaced sets oi. brushes bearing upon said commutator, means for maintaining relative rotation between commutator and brushes in synchronisni with the source,

brushes of one set, and a regulating, vcoil connected to the other set. i

6. An alternating current source, a magnetic circuit, connections for exciting the circuit from the source, a plurality of conducting coils in inductive relation to the magnetic circuit; commutating' devices for said coils including two relatively displaced sets of brushes, means for maintaining relative rotation of the brushes and coils in synchronism with the source, means for fixing the potential diilercnee between the brushes of one set, and means for utilizing the current i'rom the other set.

7. An alternating current circuit, a magnetic circuit, a Arluding in inductive relation to the magnetic circuit'and its comnmtator; a set of.brushes for said commutator; means for applying to the magnetic circuit a source of excitation proportional to the current in the alternating; current circuit; means for maintaining between said brushes a direct current difference of potential independent of the alternating current excitation, a second set set, a regulating coil connected to the second set of brushes, and means i'or producing relative rotation of brushes and commutator.

In testimony whereof I havehereunto signed my name.

.1. LESTER WOODBRTHHE,

Witnesses W. J. .Twercsox,

K. M. (ilLLlGAN.

current lines and with the booster field regulating coil,

means for fixing the potential difference between the oi brushes for the commutator displaced from the tirst- 

